Carpentry and Woodworking - stairs stained and polyed

i have installed new interior stairs in my house and have stained them and polyed them. my problem is the first layer of poly has something that looks like bubbles or round circles, what should i do???

Bubbles in the finish usually indicate that the trapped air could not escape before the film set up. Don't overbrush polyurethane, maintain a proper temperature, keep fans and such from blowing across the finish so it can dry at its own rate, thin the finish slightly to allow to air to escape, don't apply it too thickly.

You can sand the finish 180 - 240 grit or so to knock down the bubbles or any nibs between coats. More than one coat of polyurethane is needed anyway. Several thin coats are best.

Round circles may be "fish-eye", a contamination caused by silicone and silicone-based products and oils. Nothing will adhere to pure silicone.

Since the finish is dry, scrub with clean cloths dampened with mineral spirits to remove any oil, grease, or wax that may remain. Try to coat over the area with the round circles to see if this solves the problem.

It is helpful to wipe any piece of wood to be stained and finished with a cloth dampened with mineral spirits to be sure that wax, oil, grease, glue, handprints, and the like are not present before applying the stain. Contaiminated places will not take the mineral spirits, and the sites will show up as undampened wood. Then you can take steps to clean the wood thoroughly.

Hope this helps.